Advocates want asylum-seeker death inquiry

Prime Minister Malcolm Turnbull has again defended his government's policy on asylum seekers who arrive by boat after one man died and detainees rioted over his treatment.

Refugee advocates now want a royal commission into medical care at Australia's offshore detention centres on Papua New Guinea's Manus Island and Nauru in the Pacific.

A 27-year-old Sudanese man, Faysal Ishak Ahmed, died on Saturday in Brisbane after being airlifted from Manus the day before.

"It appears that Faysal did not receive appropriate treatment for his condition and we now have another death that was likely to have been entirely avoidable," National Justice Project principal solicitor George Newhouse said on Sunday.

Mr Ahmed collapsed at the centre on Thursday and had been ill for more than six months, according to a fellow refugee on the island.

"Every day Faysal went to medical asking for help. They did not help him," Behrouz Boochani said in a statement from Manus Island released by the Refugee Action Coalition.

"A few days ago a nurse ... told Faysal that he was fine and didn't need medical treatment."